Portable jump starter



FIG. 1 is a front perspective view of a portable jump starter, showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left elevation view thereof;

FIG. 6 is a right elevation view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The broken lines shown in the drawings depict portions of the portable jump starter that form no part of the claimed design. 

CLAIM The ornamental design for a portable jump starter, as shown and described. 